As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
RTFL DUE TO SIGNIFICANT VIBRATION IN LEFT ENGINE AFTER TAKEOFF. COULD NOT ADVANCE POWER W/O VIBRATION INCREASING. 3RD STAGE LPT BLADE FRACTURED. THE 3RD STAGE LPT BLADES AND VANES WERE SULFIDED. DURING DISASSEMBLY A BOLT FOR THE OUTER DUCT WAS FOUND FRACTURED. THE LOOSE DUCT REDUCED AIRFLOW TO THE BLADES AND THE ON-GOING BLADE SULFIDATION CAUSED THE FAILURE OF BLADE.